You Learned Rails...Now What?

If you learned Rails but you still feel like you could be doing a lot better...

...if you don't feel very confident in your Ruby skills...

...if you'd like to earn more, write better code & be proud of your work...

...then this could be the most important message you'll read today.


my name is Jesus Castello & I've been a Ruby developer for over 6 years.

I've spent the last 2 years teaching Ruby & I'd love to help you become a better Ruby developer.

Most of my students feel a lack of confidence because their Ruby skills are lacking.

They just rushed their learning & are missing vital information about how Ruby works...

...if your Ruby skills are lacking you're gonna have a hard time gettings things done, fixing things when they go wrong & solving real-world problems.

That's oK if you are just doing this as a hobby...

But if you want to get paid & feel good about your work you need to take this seriously.

How do you do that?

By learning everything you can about Ruby!

Here's a fact:

There's a lot more to Ruby than just variables & conditional statements.

You don't wanna miss on all the really good stuff.

When you Understand Ruby Better...

You'll be able to write better code, enjoy your work more & be proud of what you do.

The problem is:

It's hard to know exactly what you need to learn...

...and it's even harder to find all the information you need in one place!

That's why I invested over 100 hours of my time to put together a resource for you...

A resource which:

  • ​Helps you build a solid foundation of Ruby skills
  • ​Bridges the gap between the fundamentals & more advanced concepts
  • Shows you the tools, ideas and examples you need to understand things better

The resource I'm talking about is Ruby Deep Dive, the book for serious Ruby developers.

It's Not Only a Ruby Book, It's a Complete Package

Ruby Deep Dive is a complete package to help you build a solid Ruby foundation, bridging the gap between the fundamentals & more advanced concepts.

This is what you get:

  • A 170-page PDF eBook
  • ​100+ Code Examples You Can Copy & Paste For Quick Learning
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    8 Printable Quick-Reference Mindmaps
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    A List of Resources to Help You Keep Growing As a Developer
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    Answers to All Your Ruby Questions Via Email

Mary Katherine



“I've been reading Ruby Deep Dive as I have time and finding it to be SUPER​​​​ helpful​​​​​.

It's exactly the 'next step' I needed after doing all the beginner tutorials. Thanks for writing it!!! :)“

Some of the things you'll discover inside Ruby Deep Dive:

  • What are blocks, procs & lambdas, how they work & how to use them for maximum benefit!
  • ​Ruby tricks, tips & advice to help you become a better developer.
  • ​How to make your Ruby programs faster
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    Why Enumerable is the most important Ruby class & how to get the most out of it!
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    One thing you need to stop doing now unless you want to look like a beginner developer
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    A review of the core Ruby classes so you aren't missing out on something important!
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    Exactly why this hidden Ruby class makes it possible for Ruby to have class methods (this is the key to understanding how Ruby works under the hood)
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    ...and a few other things that you will not find on your average Ruby book

Imagine being able to understand every line of code in your project...

...and learning to use the full power of Ruby so you can become more confident, understand how things work & write better code.

Ruby Deep Dive will help you do that.

Click the yellow button below & grab your copy today :)


(You will instantly receive a download link to a zip file containing the PDF of the book plus all the learning resources.)


I know you'll love this book because I put a lot of work into it, but if for whatever reason you aren't happy with it... problem!

Let me know within 60 days & I'll give your money back.

Table of Contents

  1. Using Pry to Learn Ruby
    • The Power of Pry
    • Where did this method come from?
    • Pry Tricks & Tips
    • Debugging using Pry
  2. Understanding Exceptions
    • What are Exceptions and Why They Happen
    • Understanding Stack Traces
    • Using Exceptions
    • At Exit
    • Custom Exceptions
    • Common Errors Guide
  3. Working with Data
    • Strings
      • Putting Strings Together
      • Manipulating Strings
      • Working with Characters
      • Immutability and Frozen Strings
    • Arrays
      • Let's review: What's an Array?
      • Basic Operations
      • Iterating Over Arrays
      • More Array Operations
      • The Splat Operator
      • Operations Involving Multiple Arrays
    • Hash tables
      • Using Hash Tables
      • Basic Usage
      • Iterating Over Hash Values
      • How to Use Default Values (and avoid this problem)
      • Using Fetch and Merge
      • The Dig Method (new in Ruby 2.3)
    • Ranges
      • Inclusive & Exclusive ranges
      • Iterating over ranges
      • Stepping
      • Random number within a range
    • Data Serialization
      • CSV
      • JSON
      • YAML
  4. The Ruby Object Model
    • Introduction to the object model
    • Super-classes
    • The singleton class
    • Ruby Internals
    • Constants in Ruby
    • Constant Lookup
    • Ruby Method Sugar
  5. Procs & Lambdas
    • What's a block & how to use them
    • The Yield Keyword
    • Lambdas vs Blocks
    • Closures
    • Using to_proc
  6. Understanding Require
    • Why do we need require?
    • How Ruby gems are required
    • Require vs Require Relative vs Load
  7. Regular Expressions
    • What is A Regular Expression?
    • Character ranges
    • Capture groups
    • LookAhead & LookBehind
    • Ruby methods for working with regular expressions
  8. Modules
    • What is a module?
    • How are modules different from classes?
    • 5 ways to use modules
  9. Enumerable
    • What is Enumerable?
    • 7 Ruby methods every serious Ruby developer should know
    • How does the inject method work? (in detail)
    • How to include Enumerable in your own class
    • What are Lazy Enumerators & when to use them
    • What are generator objects? (lesser known feature)
  10. Using Sinatra
    • Sinatra fundamentals
    • How to write a simple API
    • Interacting with a database
  11. Performance
    • Benchmarking vs Profiling
    • How to make your programs faster
    • Ruby performance tools explained
  12. Comparing Objects
    • The Comparable module
    • The spaceship operator
  13. Metaprogramming
    • What is self?
    • How do you handle undefined methods?
    • Creating dynamic methods
    • Creating dynamic constants
    • Using hooks
  14. Writing a DSL
    • What is a DSL & how to implement one

 Jay Wilburn​​​​ 

Full-Stack Developer 


"This book has helped me understand things better. And I have been able to apply those learnings into some of my work."

Today is the day when you finally make a good decision & get back on track to becoming an expert Ruby developer.

Don't wait any longer & start improving your Ruby skills today!